Open an internet browser and go to https://cran.r-project.org./
Click on the Download R for Windows link.
Click on the base subdirectory link or install R for the first time link.
Click, Download R X.X.X for Windows (X.X.X stand for the latest version of R. eg: 4.1.1). At the moment of writing (16 August 2021), R 4.1.1 is the latest version. Choose the most recent one.
This save the executable .exe file.
Run the .exe file and follow the installation instructions. Default settings are fine. Without installing R, you will not be able to install RStudio and additional packages later.
If you want to watch a step-by-step tutorial on how to install R for Windows, you can watch these video here: https://www.youtube.com/watch?v=Ohnk9hcxf9M
Remember, you must have R already installed before installing Rstudio.
Open an internet browser and go to https://cran.r-project.org./
Click on the Download R for macOS link.
Click on the link for the pkg file of the latest R version and save it.
Double click the downloaded file and follow installation instructions on the screen.
If you want to watch a step-by-step tutorial on how to install R for Windows, you can watch these video here: https://www.youtube.com/watch?v=uxuuWXU-7UQ
Go to: https://www.rstudio.com/products/rstudio/download/ and click on the “DOWNLOAD” button.
Click on “DOWNLOAD RSTUDIO FOR MAC”.
Save the .dmg file on your computer, double-click it, and then drag and drop it to your applications folder.
Remember, you must have R already installed before installing Rstudio.